Field of the Invention
The present invention relates to an emergency braking system capable of braking a vehicle by more efficiently predicting forward collision and a method of controlling the same.
Discussion of the Related Art
Recently, with advances in sensor technology and control technology, functions for assisting a driver have been included in a vehicle. One of the functions is advanced emergency braking (AEB) that generates a warning or performs braking when there is a possibility of collision with a forward obstacle.
A normal emergency braking system calculates an expected collision time using target information regarding preceding vehicles and pedestrians, obtained from a forward radar and an imaging device, and generates a warning sound and performs braking control, such as partial braking and engine torque reduction, and full braking, based on a classified danger level. A danger level may be divided into a plurality of detailed levels based on characteristics of the system and may be divided by a lookup table value prestored in the system based on an expected collision time and relative speed with a target obstacle.
For example, a relationship between operation, speed, and an expected collision time when a danger level is divided into three levels will now be described with reference to FIGS. 1A and 1B of the related art. FIGS. 1A and 1B illustrate classification of a danger level and an operation performed according to the danger level in a normal emergency braking system of the related art.
Referring to FIG. 1A, when the danger level is classified into first warning, second warning, and third warning, different actions such as warning sound generation, partial braking, and full braking may be performed based on the respective danger levels and deceleration and acceleration are substantially affected by each danger level.
In addition, as illustrated in FIG. 1B, a timing at which an operation corresponding to each danger level is performed may be determined based on relative speed and an expected collision time between a current vehicle and a forward obstacle. For example, when the relative speed is high or greater than a particular speed, warning or braking may be performed even when substantial time remains until the expected collision time and, when the relative speed is low or less than a particular speed, warning or braking may be performed when relatively less time is left unit the expected collision time.
As described above with reference to FIG. 1, warning and braking timings in the normal emergency braking system are predetermined and only a variable offset may be applied to the warning timing and the braking timing based on input of a system setup command by a driver. Therefore, when warning is generated in a situation where the driver determines that a current state is not dangerous or when braking is performed in a situation where the driver is capable of sufficiently avoiding a current situation or performing braking, driver inconvenience may occur.